{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2023-2911",
        "ASSIGNER": "security-officer@isc.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "If the `recursive-clients` quota is reached on a BIND 9 resolver configured with both `stale-answer-enable yes;` and `stale-answer-client-timeout 0;`, a sequence of serve-stale-related lookups could cause `named` to loop and terminate unexpectedly due to a stack overflow.\nThis issue affects BIND 9 versions 9.16.33 through 9.16.41, 9.18.7 through 9.18.15, 9.16.33-S1 through 9.16.41-S1, and 9.18.11-S1 through 9.18.15-S1."
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "ISC",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "BIND 9",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<=",
                                            "version_name": "9.16.33",
                                            "version_value": "9.16.41"
                                        },
                                        {
                                            "version_affected": "<=",
                                            "version_name": "9.18.7",
                                            "version_value": "9.18.15"
                                        },
                                        {
                                            "version_affected": "<=",
                                            "version_name": "9.16.33-S1",
                                            "version_value": "9.16.41-S1"
                                        },
                                        {
                                            "version_affected": "<=",
                                            "version_name": "9.18.11-S1",
                                            "version_value": "9.18.15-S1"
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://kb.isc.org/docs/cve-2023-2911",
                "refsource": "MISC",
                "name": "https://kb.isc.org/docs/cve-2023-2911"
            },
            {
                "url": "http://www.openwall.com/lists/oss-security/2023/06/21/6",
                "refsource": "MISC",
                "name": "http://www.openwall.com/lists/oss-security/2023/06/21/6"
            },
            {
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U3K6AJK7RRSR53HRF5GGKPA6PDUDWOD2/",
                "refsource": "MISC",
                "name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U3K6AJK7RRSR53HRF5GGKPA6PDUDWOD2/"
            },
            {
                "url": "https://www.debian.org/security/2023/dsa-5439",
                "refsource": "MISC",
                "name": "https://www.debian.org/security/2023/dsa-5439"
            },
            {
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SEFCEVCTYEMKTWA7V7EYPI5YQQ4JWDLI/",
                "refsource": "MISC",
                "name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SEFCEVCTYEMKTWA7V7EYPI5YQQ4JWDLI/"
            },
            {
                "url": "https://security.netapp.com/advisory/ntap-20230703-0010/",
                "refsource": "MISC",
                "name": "https://security.netapp.com/advisory/ntap-20230703-0010/"
            }
        ]
    },
    "source": {
        "discovery": "INTERNAL"
    },
    "work_around": [
        {
            "lang": "en",
            "value": "Setting `stale-answer-client-timeout` to `off` or to a non-zero value prevents the issue.\n\nUsers of versions 9.18.10, 9.16.36, 9.16.36-S1 or older who are unable to upgrade should set `stale-answer-client-timeout` to `off`; using a non-zero value with these older versions leaves `named` vulnerable to CVE-2022-3924.\n\nAlthough it is possible to set the `recursive-clients` limit to a high number to reduce the likelihood of this scenario, this is not recommended; the limit on `recursive-clients` is important for preventing exhaustion of server resources. The limit cannot be disabled entirely."
        }
    ],
    "exploit": [
        {
            "lang": "en",
            "value": "This flaw was discovered in internal testing. We are not aware of any active exploits."
        }
    ],
    "solution": [
        {
            "lang": "en",
            "value": "Upgrade to the patched release most closely related to your current version of BIND 9: 9.16.42, 9.18.16, 9.16.42-S1, or 9.18.16-S1."
        }
    ],
    "impact": {
        "cvss": [
            {
                "version": "3.1",
                "attackVector": "NETWORK",
                "attackComplexity": "LOW",
                "privilegesRequired": "NONE",
                "userInteraction": "NONE",
                "scope": "UNCHANGED",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "availabilityImpact": "HIGH",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "baseScore": 7.5,
                "baseSeverity": "HIGH"
            }
        ]
    }
}